The invention relates to improvements in methods of and in apparatus for regulating the flow of one or more gas streams, especially for regulating the flow of malodorous air from so-called self-ventilating toilets. More particularly, the invention relates to improvements in methods of and in apparatus for regulating the flow of gases through a control chamber or vessel wherein a gas-admitting inlet is normally sealed from a gas-discharging outlet by a body of sealing liquid (normally water).
In heretofore known apparatus (such as self-ventilating toilets), the path for the flow of malodorous gases from the inlet to the outlet of the control chamber is established in response to actuation of a knob or another manually operable handgrip member so as to lower the level of the supply of sealing liquid in the chamber beneath that which is necessary to establish a liquid seal between the gas-admitting inlet and the gas-discharging outlet of the control chamber. Once the path for the outflow of air from the interior of the toilet bowl is established, the bowl is used and its contents are flushed down the drain pipe. During such interval of time, malodorous gases are caused to flow through the control chamber and into a gas-discharging conduit which is connected to the control chamber and evacuates gases from the room in which the bowl is installed. The handgrip member (such as the aforementioned knob or a lever) is similar to the handgrip member which must be actuated in order to flush the contents of the bowl down the drain pipe so that the user of a toilet employing such self-ventilating bowl is likely to confuse the actuating means for ventilation with the actuating means for flushing. Thus, flushing can take place prior to or without the establishment of a path for evacuation of malodorous air from the bowl. This is aggravating when the self-ventilating toilet is installed in a passenger plane, in a terminal, in a restaurant, in a school or in any other establishment wherein one and the same toilet is likely to be used at frequent intervals.
As a rule, presently known self-ventilating toilets are equipped with mechanical means for effecting or initiating the evacuation of sealing liquid from the control chamber, and such mechanical means employ large numbers of moving parts which are subject to extensive wear leading to short useful life of the apparatus and/or to frequent malfunctions. Moreover, and as mentioned above, the actuating members for such apparatus are similar to and are often placed adjacent the actuating members which must be manipulated in order to flush the contents of toilet bowls down the drain. This is confusing to a person who is not familiar with the manipulation of a self-ventilating toilet.